2-D inner-shelf current observations from a single VHF WEllen RAdar (WERA) station

G. Voulgaris; N. Kumar; K.-W. Gurgel; John C. Warner; Jeffrey H. List

doi:10.1109/cwtm.2011.5759525

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2-D inner-shelf current observations from a single VHF WEllen RAdar (WERA) station

G. Voulgaris·N. Kumar·K.-W. Gurgel·John C. Warner·Jeffrey H. List

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Abstract

The majority of High Frequency (HF) radars used worldwide operate at medium to high frequencies (8 to 30 MHz) providing spatial resolutions ranging from 3 to 1.5 km and ranges from 150 to 50 km. This paper presents results from the deployment of a single Very High Frequency (VHF, 48 MHz) WEllen RAdar (WERA) radar with spatial resolution of 150 m and range 10-15 km, used in the nearshore off Cape Hatteras, NC, USA. It consisted of a linear array of 12 antennas operating in beam forming mode. Radial velocities were estimated from radar backscatter for a variety of wind and nearshore wave conditions. A methodology similar to that used for converting acoustically derived beam velocities to an orthogonal system is presented for obtaining 2-D current fields from a single station. The accuracy of the VHF radar-derived radial velocities is examined using a new statistical technique that evaluates the system over the range of measured velocities. The VHF radar velocities showed a bias of 3 to 7 cm/s over the experimental period explainable by the differences in radar penetration and in-situ measurement height. The 2-D current field shows good agreement with the in-situ measurements. Deviations and inaccuracies are well explained by the geometric dilution analysis.

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Source-reported bounding extent: 35.18166571475282° to 35.285984736065764° latitude; -75.66558837890625° to -75.49667358398438° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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G. Voulgaris, N. Kumar, K.-W. Gurgel, John C. Warner, Jeffrey H. List. 2011. 2-D inner-shelf current observations from a single VHF WEllen RAdar (WERA) station. https://doi.org/10.1109/cwtm.2011.5759525

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